1.0 link Rainbow Dash Network http://rainbowdash.net/ Patch (patch) http://rainbowdash.net/patch http://rainbowdash.net/notice/886740 Okay, got it. There's a piston and an air chamber in Nerf guns. The piston is used to compress the air in the cylinder, and the compressed air is used to fire the dart. In a direct plunger system, the piston moves. In a reverse plunger system the *chamber* is the thing that moves.